[flatland] Give client threads an optional role.

Bug: 401550323
Change-Id: I6241f2e2b1824e376c89d391781aae218dadb69d
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1227669
Commit-Queue: Auto-Submit <[email protected]>
Reviewed-by: Caroline Liu <[email protected]>
Fuchsia-Auto-Submit: Adam Perry <[email protected]>

Author: anp

src/ui/scenic/lib/flatland/BUILD.gn

@@ -59,6 +59,7 @@ source_set("flatland") {
 
   deps = [
     "//sdk/lib/fidl/hlcpp",
+    "//sdk/lib/scheduler/cpp",
     "//sdk/lib/sys/cpp",
     "//sdk/lib/ui/scenic/cpp:cpp",
     "//src/lib/fsl",

src/ui/scenic/lib/flatland/flatland_manager.cc

@@ -9,6 +9,7 @@
 #include <lib/async/default.h>
 #include <lib/fidl/cpp/hlcpp_conversion.h>
 #include <lib/fit/function.h>
+#include <lib/scheduler/role.h>
 #include <lib/trace/event.h>
 
 #include <utility>
@@ -109,6 +110,12 @@ scheduling::SessionId FlatlandManager::CreateFlatland(
                           this->alive_sessions_--;
                         });
       });
+  async::PostTask(instance->loop->dispatcher(), []() {
+    zx_status_t status = fuchsia_scheduler::SetRoleForThisThread("fuchsia.graphics.flatland");
+    if (status != ZX_OK) {
+      FX_LOGS(WARNING) << "Failed to apply profile to flatland thread: " << status;
+    }
+  });
   instance->impl = NewFlatland(
       instance->loop, std::move(request), id,
       std::bind(&FlatlandManager::DestroyInstanceFunction, this, id), flatland_presenter_,